Electric regulator



Oct. 13, 1936. L. G. TuBBs 2,057,458

ELECTRIC REGULATOR Filed July 26, 1933 WITNESSES: INVENTOR Lesfer G. 7Z/bb5.

BY g g ATTORNEY Patented a. 13, 1936 PATENT OFFICE ELECTRIC REGULATOR Lester G. Tubbs, Wilkinsburg, Pa., asslgnor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania Application July 26, 1933, Serial No. 682,254

2 Claims.

My invention relates to electric regulators and particularly to contact making relays therefor, and has application to primary relays for use with induction regulators, although it is not limited to such use.

Primary relays used for controlling electric regulators comprise an armature or contact carrying arm that is operated by a solenoid energized in accordance with the electric quantity to be regulated, and which operate circuit closing contact members and mechanism controlled thereby -for returning the regulated quantity to its desired value upon variations therefrom. Since the regulated quantity varies gradually, it is frequently desirable to have some device which provides for positively operating the contact members to insure a definite make and break of the circuits controlled thereby. It is customary to employ electromagnets energized by a circuit through the contacts of the relay. These, However, are not energized until the relay contact members close in the one or the other direction.

It is an object of my invention to provide a means for closing and interrupting the control circuits of a regulator that is simple in construction, efiicient and reliable in operation, and low in cost.

Another object of my invention is to provide means that is positive in operation for causing the engagement and separation of the contact members that govern regulator control circuits.

Other objects of my invention will become evident from the following detailed description, taken in conjunction with the accompanying drawing, in which:

Figure 1 is a diagrammatic illustration of apparatus and circuits arranged in accordance with one embodiment of my invention; and

Fig. 2 is a view of a portion of a modified form of the primary relay shown in Fig. 1.

While the present invention may be adapted to other uses, it is particularly useful, as shown in Fig. l, for controlling the operation of an induction regulator l comprising a primary or stator winding 30 connected between the conductors 3 and 4 of a circuit to be regulated, and a secondary or rotor winding 3| connected in series with one of the conductors 4 and inductively related to the primary winding. The position of the rotor winding is determined by operation of a motor 2. A primary relay 33 is pro-- vided to actuate secondary relays 20 and 2| to control the operation of the motor 2 in accordance with variations of a regulated quantity, such as voltage, of the circuit 3-4 for the purpose of causing the regulator l to maintain the voltage of circuit 3-4 substantially uniform at a desired value. The relay 33 comprises a main actuating coil or solenoid 5 that is connected, preferably, as here shown, through a transformer 6 to the conductors 3-4 of the regulated circuit. The degree of energization of the solenoid 5 depends on the valueof the voltage in the circuit 3-4. Cooperating with the solenoid 5 is a movable core I that is actuated thereby and is suspended from one end of a lever 8, that is pivotally supported at. 9. The other end of the lever B is provided with, pole pieces 10 and H of magnetizable material. The lever 8 carries contact members I2 and I3, that cooperatewith the stationary contact members 15 and [6, respectively, to close motor control circuits for operating the motor 2 in the one or in the other direction. A spring I4 is attached to the lever 8 and partially overcomes the efiect of the downward pull caused by the weight of the core I, which is pulled upwardly by the magnetic action of the coil 5. The tension of the spring is so adjusted that the lever will be in its illustrated or open circuit position when the voltage of the circuit 34 is at its desired value. Adjacent the armature pole pieces Ill and II, a stationary permanent magnet ll, having two or more poles I8, is so disposed as to cooperate with the moving armature poles l6 and ll. If the armature pole pieces I!) and H are disposed adjacent two of the poles l8 of the stationary magnet H the magnet will hold the armature against movement from that position until an appreciable moving force is obtained, at which time, the armature poles l0 and H will slip to the next set of stationary poles It. If the lever B is in one of its stable positions, such, for example, as the illustrated or open circuit position of the relay, and a force is exerted sumcient to move it to its next stable position, it will, as soon as the pole pieces l0 and II are moved sufliciently from one position, be positively biased to the next position. For example, if the right hand end of the lever 8 is moved in either direction away from its mid-position sufiiciently to overcome the attraction of the two central poles of the magnet H for the pole pieces I0 and II they will be attracted by a pair of end poles of the magnet, thus forcing the lever 8 into one of its circuit closing positions. This action gives a very definite movement of the contact carrying lever 8 from a gradually varying force, and insures the necessary pressure between cooperating contact members.

In the operation of the primary relay 33, the

varying voltage between conductors 3 and 4 causes the coil 5 to exert a varying pulling force upon the core I tending to rotate the lever 8 about the pivot 9 in a clockwise direction and the weight of the core tends to cause its rotation in the opposite direction, so that the one or the other of the contact members l2 or I3 is caused to engage its associated stationary contact member l5 or Hi. The movable armature poles l0 and II will be attracted by the stationary poles l8 of the permanent magnet H, and upon engagement of one pair of contact members the lever 8 is biased to force the movable contact member into positive engagement with its cooperating stationary contact member until the regulating force causes an opposite movement of the lever 8.

The stationary and movable contact members |2, I3 and I5, l6, respectively, upon engagement and separation, control circuits for eiTecting the energization of the control windings of the two secondary relays 2D and 2| which, in turn, control the direction of rotation of the motor 2. The current for energizing thewindings and for the operation of the motor may be derived from any suitable source, as, for instance, from the supply conductors 34.

Upon engagement of the contact members I2 and IS, a circuit is closed that may be traced from the middle supply conductor 34, through conductor to lever 8, through contact members l2 and I5, conductor 38. the operating winding of the relay 20 and conductor 38 to the upper supply conductor 34. The above traced circuit, when energized, causes the relay 20 to close a circuit to operate the motor 2 in a voltage increasing direction. This circuit may be traced from the upper phase conductor 34, through conductor 38, contact members 39 and 40 of the relay 20, and conductor 4| to the upper terminal of the motor 2, and from the lower motor terminal through conductor 42, contact members 43 and 44 of the relay 20 and the conductor 45 to the lower phase conductor 34. The middle phase conductor 34 is permanently connected to the middle terminal of the motor 2.

Similarly, engagement of the primary relay contact members |3 and |6 closes a circuit that causes the secondary relay 2| to close, which may be traced from the middle phase conductor 34, through conductor 35, contact members l3 and I6, conductor 46, the winding of relay 2| and by conductor 38 to the upper phase conductor 34. Upon closing of the relay 2| a circuit is completed from the lower phase conductor 34, through conductor 45, contact members 41 and 48 of the relay 2|, and conductor 4| to the upper motor terminal, and from the lower motor terminal, through conductor 42, the contact members 49 and 50 of the relay 2|, and the conductor 38 to the upper phase conductor 34, thus causing the motor 2 to operate in a voltage decreasing direction.

Fig. 2 shows the use of a relay lever having a single movable armature pole piece I9 instead of the two poles l0 and H used in Fig. 1. The cooperating magnet 5| is provided with three poles, instead of four as is the magnet H of Fig. 1. This construction may be used where a relatively small pull on the armature is required.

It is apparent that the illustrated means for making and breaking electric circuits by causing positive movement of the circuit controlling contact members may be applied to such contact members operated by a float valve, thermostat, variable pressure, or other similar device actuated by a gradually varying force.

It will be apparent to those skilled in the art that modifications may be made in the apparatus described without departing from my invention and I do not wish to be limited, except by the accompanying claims.

I claim as my invention:

1. A relay device comprising, in combination, a stationary contact, a movable contact adapted to co-operate therewith, electro-responsive means for actuating said movable contact, a magnetic pole piece carried by said means, and means comprising a permanent magnet .having alternate north and south poles cooperating with said first-named pole piece to provide a positive make and break action for said contacts.

2. A relay device comprising, in combination, a stationary contact, a movable contact adapted to cooperate therewith, an armature for actuating said movable contact having a bifurcated end of magnetizable material, and means comprising a permanent magnet having a plurality of poles spacedly positioned along the line of travel of said bifurcated armature end in cooperative relation thereto to provide a positive engagement and separation of said device contacts.

LESTER G. TUBBS. 

